A tight bottom.
Eaaasssssyyy. I don’t know what you were thinking but a tight bottom is what most of us strive to achieve in our mixes. And one way to help your low end is through the selected use of EQ shelving and filter cuts. Let’s take a look at a few techniques that might help you clean the junk out of your trunk.
OK. Think about all the instruments that take up sonic space in the bottom of the typical song. You’ve got the kick, bass, toms, guitars, keys, and sometimes strings. Add to that additional sampled bass and kicks and that’s a lot of info fighting for a piece of the same action. Whether it’s through an analog outboard EQ or software plug-in, you’ve got the tools at your fingertips to get the job done.
The first thing I do is simply “focus” on the foundation of the mix, typically in the 250Hz range and below. As is often said, a problem identified is half solved. Listen to what’s happening “down there” — can you clearly hear the thump of the kick in relation to the bass? Is the low end of acoustic or electric guitars muddying up the situation? It’s at this point that I begin to assess the tracks and start cutting frequencies.
Typically, I will apply a gentle 150Hz shelving EQ (Example 1) to all guitar and keyboard parts in my mixes (which I have presets ready for). Remember, a shelving equalizer, unlike a parametric or linear, affects the entire range below (or above) the specified frequency. I’ll also place the same type of EQ on the toms of a drum kit — all in the effort to clarify the kicks position in the song. It’s important at this stage to listen to these tracks both in solo mode and within the mix, as sometimes I remove too much bottom making the sound wimpy — which is easily fixed by accordingly adjusting the shelving frequency.
Next I’ll work with the all-important bass (or basses) and kick (or kicks) to sit one “on top” of the other. By that I mean if the kick is hitting the sub frequencies in the 60–100Hz range, I’ll try to get the bass to drive at the 100–130Hz range. Depending on the type of tune, you may have to reverse the situation — but you get the point.
And in order to get this to work, I most often use a full-function EQ that has a separate filtering section — such as the Sony Oxford, Universal Audio Cambridge, McDSP FilterBank plug-in, or my Manley Massive Passive outboard unit. A high-pass (or low-cut) filter will pass the highs past the selected frequency — great for pulling out unnecessary rumble and thumps. The responses are gentler on filters with lower numbers (6 dB/octave), and get steeper and more aggressive as the numbers increase (36 dB/octave). Sometimes though, I’ll simply use the LF shelving section from EQs such as the Waves Renaissance or the URS S Series to get the job done — in combination with low-cut filters. You’ll of course have your own preferences.
Often, there are one or more loops in a song with no control over the kick. When this is the case, I’ll typically use multiple stages of cuts and filtering (Example 2). Filtering the bottom of Loop 1 around 60Hz, I’ll also shelve around 160Hz, making room for the kick in the second loop. Again, every situation will be different, but overall this method tends to work quite well. Certainly the ultimate goal is to have each heard clearly — while maintaining the punch needed to push the bottom of the tune along. Don’t forget to monitor at both soft and loud volumes (and with headphones) so you’re not fooled by the bass response of your room.
If you think in terms of cut, not boost, you’ll find your rhythm section will sound punchier. Of course, there are no rules here, and you should do whatever it takes to get the job done — but cutting is a good place to start. When it comes time to boost, I’ll typically punch up (if need be) 120Hz with a very tight Q on the bass and 10Hz on the kick, with a slight 10K boost for clarity. Again, add ingredients to taste.
And after running through the above-mentioned tracks, I will apply a Waves PAZ analyzer across the stereo bus, to visually look at the energy of the mix. I’ll then run through just about every track in the mix to “watch” the low end. I’ve discovered a lot of sub offenders using this method, such as Fender Rhodes parts, room mics, and the rumble of closely miked guitar cabinets.
With a little creative use of EQ and filtering, you, too, can be proud to show off your bottom! In public, no less!